信号与系统实验傅里叶变换

下载后可任意编辑信号与系统实验10.1 利用 fourier 函数求下列信号的傅里叶变换 F(jw)，并用 ezplot 函数绘出其幅度频谱|F(jw)|和相位频谱 d（w）。<1>f1(t)=(sin(2*pi*t)/(2*pi*t))2syms t phase im ref=sin(2*pi*t)/(2*pi*t);F=fourier(f);subplot(3,1,1)ezplot(f);title('Ôͼ')axis([-pi pi -0.3 1.1])subplot(3,1,2)ezplot(abs(F))title('·ù¶Èͼ')axis([-3*pi 3*pi 0.3 0.6])im=imag(F); re=real(F); phase=atan(im/re);subplot(3,1,3) ezplot(phase) title('Ïàλͼ') axis([-3*pi 3*pi -0.5 0.5])<2>f2(t)=sin(2*pi*(t-2))/(2*pi*(t-2))syms t phase im ref=sin(2*pi*(t-2))/(2*pi*(t-2));F=fourier(f);subplot(3,1,1)ezplot(f);title('Ôͼ')axis([-pi 2*pi -0.3 1.1])subplot(3,1,2)ezplot(abs(F))title('·ù¶ÈÆ×')axis([-3*pi 3*pi 0.3 0.6])im=imag(F);re=real(F); phase=atan(im/re);subplot(3,1,3) ezplot(phase) title('ÏàλÆ×') axis([-3*pi 3*pi -0.5 0.5])-3-2-1012300.51t原 图-8-6-4-2024680.4w幅 度 谱-8-6-4-202468-0.500.5x相 位 谱-3-2-1012345600.51t原 图-8-6-4-2024680.4w幅 度 谱-8-6-4-202468-0.500.5w相 位 谱下载后可任意编辑10.2 试用 ifourier 函数求下列傅里叶变换的逆变换，并画出其时域波形。<1>F(iw)=1/2Sa2(w/4);syms t w F=8*(sin(w/4))^2/(w^2);f=ifourier(F,t) ezplot(f); axis([-0.8 0.8 -0.2 1.1]); title('ʱÓò²¨ÐÎ')输出为：f =-(4*fourier(cos(w/2)/w^2, w, -t) + 4*pi*t*(2*heaviside(t) - 1))/(2*pi)报错：Error using inlineeval (line 15)Error in inline expression ==> -(4.*fourier(cos(w./2)./w.^2, w, -t) + 4.*pi.*t.*(2.*heaviside(t) -1))./(2.*pi) Undefined function 'fourier' for input arguments of type 'double'.Error in inline/feval (line 34) INLINE_OUT_ = inlineeval(INLINE_INPUTS_, INLINE_OBJ_.inputExpr, INLINE_OBJ_.expr);Error in ezplotfeval (line 54) z = feval(f,x(1),y(1));Error in ezplot>ezimplicit (line 258) u = ezplotfeval(f, X, Y);Error in ezplot (line 154) hp = ezimplicit(cax, f{1}, vars, labels, args{:});Error in sym/ezplot (line 61) h = ezplot(fhandle...